Image sensors capture only illumination, not colour, by default.
Beam splitting
- A dichroic prism splits incoming light into primary colours
- A separate image sensor captures each separated beam
- Structure must be rigid and properly aligned
- Gives the same resolution for both colour and illumination
Colour filter array
Aka. CFA.
- An optical filter allows only one colour per sensing element
- Other colour components are estimated from nearby sensors
- Colour resolution is lower than illumination resolution